The present invention generally relates to control systems for controlling a supply of fluid to an integral quantity, and more particularly to a control system which is designed to precisely stop the supply of fluid when the quantity of supplied fluid reaches a desired integral quanity after a fluid supplying operation is started. The control system according to the present invention is especially suited for application in a fuel supplying apparatus of a gasoline service station.
Generally, in order to stop the supply of fuel in a fuel supplying apparatus during a fuel supplying operation so that the quantity of fuel which is finally supplied is equal to an integral quantity (for example, 20.00 liters) which is closest to the quantity of supplied fuel at the point when the fuel supplying operation is once stopped, a valve of a fuel supplying nozzle is once closed at a point before the quantity of supplied fuel reaches the integral quantity (for example, when 19.3 liters is supplied) by taking into account the time it takes for the valve of the fuel supplying nozzle to close. Thereafter, a lever of the fuel supplying nozzle is operated while monitoring an indicator so as to supply the fuel in small quantities, and the valve of the fuel supplying nozzle is closed when the integral quantity is reached. However, it is extremely troublesome to stop the supply of fluid when the integral quantity is reached, and such precise stopping of the fuel supplying operation requires skill on the part of the operator. Therefore, there is a disadvantage in that the quantity of supplied fuel may exceed the integral quantity when the operator incorrectly operates the lever of the fuel supplying nozzle.